Thirty-one other people were also alleged to have been involved in the scandal, including Zheng's wife, Liu Naixue, and his son, Zheng Hairong.

Following Zheng's sacking in 2005, the Chinese government announced a review of about 170,000 medical licences that were awarded during his tenure at the agency.

Dozens of people have died in China because of poor quality or fake drugs.

Last year, a sub-standard antibiotic, Xinfu, which was not properly sterilised, caused the deaths of 11 people.

Thirteen babies died of malnutrition in 2005 after being fed powdered milk that contained no nutritional value.

The Chinese government recently announced an urgent review of industry food standards after public alarm over a recent spate of cases.

US inspectors blamed exported Chinese pet food ingredients, contaminated with melamine, for the deaths of cats and dogs in North America.

And they recently halted shipments of toothpaste from China to investigate reports that they may be contaminated with toxic chemicals.

On Tuesday, as Zheng was sentenced, the government said a new recall process targeting "potentially dangerous and unapproved food products" would be brought in by the end of the year.

"All domestic and foreign food producers and distributors will be obliged to follow the system," Wu Jianping, of the General Administration of Quality Supervision, Inspection and Quarantine, was quoted as saying.